Calcium pyrophosphate dihydrate, hydroxyapatite, and miscellaneous crystals

Abstract

Calcium pyrophosphate dihydrate (CPPD) and hydro-xyapatite crystals are the most common calcium-containing crystals associated with joint and periarticular disorders. Deposition of these crystals is frequently asymptomatic or can be intermittently symptomatic. However, common clinical manifestations of calcium crystal deposition include acute or chronic inflammatory and degenerative arthritides, and certain forms of periarthritis. In addition to these, a number of other crystalline materials have been identified less commonly in synovial or bursal fluid. These include calcium oxalate, cholesterol, lipids, and synthetic corticosteroid crystals. © 2008 Springer-Verlag New York.